PROGEF 578 Lug butterfly valve

  Datasheet (PDF)

The Georg Fischer PROGEF Standard Type 578 Lug butterfly valve provides dependable flow isolation and precision throttling in industrial polypropylene piping systems handling aggressive chemicals, effluent treatment, and process water. Constructed with an isotactic beta polypropylene homopolymeride (beta-PP-H) disc and a high-strength glass-fibre reinforced polypropylene body (PP-GF30), this lugged valve features integrated SS316 stainless steel threaded inserts. The lug design allows direct bolting between flanges and enables safe terminal line installation or dead-end service without requiring downstream pipe retention. Manufactured by GF Piping Systems, the valve ensures exceptional structural rigidity, broad chemical compatibility, and a design life of 25 years with water at 20 degrees Celsius.

The Type 578 features an advanced double eccentric disc configuration. By offsetting the shaft axis in two distinct planes, the disc disengages cleanly from the elastomeric seal immediately upon opening, drastically reducing mechanical friction and operating torque. This geometry prevents seat wear and substantially extends overall service life under frequent operational cycling. Throttling and flow positioning are controlled via an ergonomic manual ratchet lever lockable in fine 5 degrees increments, supported by a 6-point tooth engagement system to hold disc orientation securely under fluid surges. The mechanical assembly complies fully with the technical requirements of EN ISO 16136.

Supplied across Europe by BigWeld, an authorised Georg Fischer distributor, the PROGEF 578 covers metric diameters from d63 mm up to d315 mm (DN50 to DN300) with operating pressure ratings between 6 and 10 bar. Offered with factory-configured EPDM or FKM elastomeric seals, it accommodates diverse industrial chemicals, acids, and alkaline media. The valve integrates smoothly with PP-H backing flanges and piping components, providing reliable isolation, bubble-tight shut-off, and efficient dead-end flow management across process plants and utility networks.